Manganese-Doped Cesium Lead Halide Perovskite PMMA Composite Fibrous Membranes by Electrospinning for Photocatalytic and LED Applications

Motivated by the need to reduce toxic organic dyes in wastewaters, we studied the preparation of different amounts of Mn-doped cesium lead halide perovskite in PMMA matrix (CsPb _<i>x</i> Mn_1-<i>x</i> Cl _<i>y</i> Br_3-<i>y</i> @PMMA) composite fibrous membranes (CFM) as a photocatalyst to degrade dyes via a one-step in situ electrospinning method. The composite fibrous membranes exhibit excellent environmental stability, attributed to the protective three-dimensional network structure of the electrospun fibers, which shields the internal perovskite nanocrystals from direct contact with water and light. Structural characterization by X-ray diffraction (XRD) reveals that Mn²⁺ substitution induces a phase transformation from cubic CsPbBr₃ to tetragonal CsPbCl₃. The optimal Mn/Pb ratio of 2.5:1 achieves excellent photocatalytic activity, degrading 94.7% of methyl orange (MO) within 90 min under Xe lamp irradiation with a rate constant of 0.031 min^-1, 4.6 times higher than that of the undoped sample. In addition, a single monochromatic CFM with a blue LED light source can be combined to construct a white LED (WLED) with good chromaticity coordinates (0.3267, 0.3298) and color temperature of 5775 K. This work highlights the great potential of Mn-doped perovskite composite fibrous membranes for practical photocatalytic and LED applications.